Method of blowing off boilers



' July 2s, 1925.`

1,547,703 W. G. WILSON METHOD oFflLowlNG oFF BoILERs Fi1ed oct. 19 19214 sheetslshet 1 #15T/f@ cf. www? July 2 8, 1925.

V 1,547,708 W. G. WILSON METHOD OF BLOWING OFF BOILERSA Filed 001. 19,1921 4 ShetslSheet 2 l o INVQVTOR. l I 'I l W//fe `C; W//fo/y 0 6 wwwMATTORNE 5.

w. G. wlLSoN METHOD OF BL-OWING OFF BOIL'ERS Filled OO. 19

, 1921 y 4 Sheets-Sheet 5 INI/ENTOR. #ZW/'e Q #I0/fof] @ATTORNEYS- July28, 1925.

July 2s, 1925.` 1,547,708 f w. G. WILSON l METHOD OF BLOWING OFFBOILER-S Filed oct. 19, 1921 4 sheetsheet "4; Y

fies/n face l Wafer l erg/ INVENTOR,

ATTORNEYS. 'f

Patented July 28, 1,925.

A,UNITED STATES .WIYLIE G. wTLsoN,

PATENT "oFFici-z.

OF ELIZABETH, NEW JERSEY, AS'SIGNOB T0 LOOSE SEAT VALVE COMPANY, ACORPORATION OF DELAWARE.

METHOD F BLOWING OFF BOILERS.

Application med october 19, i921. seriai No. 508,668.

`T0 all whom iii may concern; .l

rB e it known that I, WYLIE G. VtrLsoN, -a subject of the Kin of GreatBritain, and

a .resident of Eliza ethhinthe county of' matter is vin suspension, vorwater whose` 152A densityhas been increased because it carries`.matterin solution. It contemplates particularly a method by which .a portionot the watergsludge, mud, etc., may be withdrawn from. the boiler fromtime to time so that informationl may be obtained of the condition ofthe contents of the boiler, with 'particular reference .as to whetherfurther discharge through the blow-off valve will fmaterially improvethe condition of the in- Aterior of the boiler. These results are. ac-

complished under this method by providing means under whichthe How ofwater blown off maybe under control, as 'to the velocity at which theetliuent is permitted to escape, 'as to the volume withdrawn, and astothe disposition of the fluid, sludge, etc., so withdrawn. l

'This method also has for its purpose the minimizing of certainobjectionable features which are incident to boiler blow-off aspracticed, to wit: shock which is incident to thejclosing of the exhaustvalve, injury to the exhaust pipe line, particularly at points wheresuch pipe line is formed with one or 4'0 Vmoreshoulders -or elbows, aswell as effects due to the sudden heating ofthe pipe line causingexpansion, etc., all of which is incident lto the sudden rush of water,sludge, etc.,"at high temperature and great velocity through saidpipeline. The valve interposed inthe pipe line is also liable to injury,voccasioned by what is known as wire drawing when the valve is opened orclosed, and 4particularly when an effort is made to con- *trol thevelocity of eiluXc by partially clos- Aing the valvel All of theseincidents are present in the operation of blowing oli" steam boilers asat present constituted and, as stated,` it is among.I the purposes ofthis method or system to provide means and to proceed by steps or stagesto so operate said means asto overcome thesediiiiculties and toestablish a system under whicha steam boiler may be blownvloff underconditions where theeiiiuent is under perfect control, and also so thatthe operator may from time to time sample the contents of the boiler andfrom inspection of the eiiluent determine whether theboiler needs to beblown off and4 it so to what extent, etc.

Under present conditions of boiler practice, it is customary to provideveach boiler with a blow-oifvalve adjacentthe lowest point of theboiler. conditions of' the water employed in the plant, sludge, mud,scale and other impurities suspended in the water are, as the steam -isgenerated, deposited .at the bottom of the boiler. It is `important fornumerous reasons unnecessary to narrate here tore- Dependent upon the Inmodern .steam power plant practice it l is becoming more andmorecustomary to use high lpressures and large boiler1 units. Untilquite recentjtimes, boilers were seldomv operated at pressures over20Q-pounds per square inch. Today more and more fre- 'quently in newinstallations the boilers are operated at a workingpressure of 250, '300i and v350 pounds per square inch.A In large boiler units, which arealso now becoming customary, the blow-ofi' valves are seldom smallerthan 21/2 inches in diameter.-

In the'operation of such boilers under the conditions named, it will beappreciated that the temperature of the water'increases as the pressureincreases.

over, is opened, the terrific rush of water through-the valve andthrough thepip'ing,

'and the discharge of quantities of very hot When the blow-off valve ona boiler'under, say 250 pounds or detrimental and -even dangerousconsequences. Experience demonstrates that it is often desirable tooperate the blow-off valves on boilers atleast once a day and insomecases more frequently. It will be understood that Water drawn fromthe boiler under the high pressures stated above is at a highertemperature and its expulsion is at a greater velocity than is the casein boilers operating at the low`er pressures customary until recentyears. It will be understood, therefore, that the diliiculties anddangers incident .to boiler blow-off under conditions of high pressure(and consequent high temperaturei are greater than they have heretoforebeen under conditions of lower pressure' and consequent lowertemperature.

Under the conditions abovenained when -it is desired to blow off aboiler, the-blowoff valve is opened for aspace of time which in theestimation of the engineer in charge will be suiiicient to clear theboiler of sludge, scale, water of too great density, etc., as far as itis possible and advisable to remove, these through the blow-olf valve.In the operation of blow-olf valves under the high pressures mentionedconsiderable danger to the lifeand limb of the operator is incident,both owing to the fact that the suddenA eluX at high velocity (due tothe high pressure) of this water carrying gritty particles wears out thevalves and the pipe line at bends, and also due to the fact thatthe-sudden flow of this high temperature water, through the pipe linespreviously at a much lower temperature, produces a sudden'expansion ofthose pipe lines, thus leadl ing to leaks, etc.; further thelarge'valves the valve and the conditions of pressure and the timelduring which the valve is perinitt-ed to remain open. There is atpresent no satisfactory method by which the operator can tell whetherthe blow-off valve has from Vthe boiler through tlieblow-,off of valvehas been discharged; or whether the valve has been open too. long sothat in addition to the necessary discharge of dense water, etc., anunnecessary quantity of hot Water has been discharged, thus occasioningan unnecessary loss of money.

control the blow-off operation, so that the amount of fluid withdrawnmay be definitely and positively limited, so that the con- 1 dition ofthe sludge or'mud in the boilers may be from time to time inspectedunder Such conditions that the fluid contained at the base of the boilerwill be brought in position where it-can be conveniently observed andtested, and. so operated as to relieve detrimental stresses and strainson the interposed blow-olf' valve operating mechanism, and alsoto-minimize the shock velement incident to closing such valve;A in

other words so taining the violent elements above referred to as tobring the same under the absolute control and dominion of the-mastermind operating the boilers.

For the purpose of putting into operation a method or system of boilerblow-olf which is the subject-matter of this invention, it is essentialthat I employ certain Imechanisms, all of which are old in their genericconstruction but which, when combined, form the means by which thismethod is performed. In the following drawings and description thereof`I have shown one form of mechanism which I regard as adapted for thepurpose of carrying 'out this' method.` but it will be obvious to thoseskilled in the art that other foiins of apparatus could be employed forthis purpose.

Figure 1 is a diagrammaticelevation of the preferred 'forni of boilerinstallation employed in the carrying out of the method of thisinvention.

Figure 2 is a diagrammatic plan view of the showing of `Figure 1Q`Figure 3 is a diagrammatic side elevation of a slightlyv modified formof construction. V

Figure 41 isa diagrammatic front elevation ofthe construction shown inFigure 3.

Figure' is a diagrammatic showing 'of particular tank constructionley-means of which certain features of the invention may be practiced.

Figure 6 is a showing similar to that of Figure 5, but showingadditional operating parts for the accomplishment of r further featuresof the invention. 'i

Figure 7 is a front elevationof the construction shown in Figure 6.Figure 8 shows diagranimatically a modified `form of boiler blowoffsystem by which the method of this invention may be practiced.

Figure 9 is an elevation the sameas Figitu) ieul

ure 1 vvith a different arrangement of supy' ply and exhaust conduitsand valves for tank D.

Referringfirst to the system diagramfrnatically illustrated in Figures 1and '2, "A andB designate 4 tWoboilers Aof a battery I a and b,respectively. Adis'charge pipe c leads from the tank to the sewer andincludes a drain valve C of any suitable type.'

The tank D, is connectedby a pipe efte the steam space -F above'theWater level of theboiler, either directly 'or through the main steamheader valve F 'and the pipe e includesl a valve E, the function ofvvh'ieh is to control the passage 'of steam from the steam space F ofthe boiler tothe balance tank and vice versa. The pipe e may alsoinclude an additional valve f: 'adjacent the point of connection to themain steam header, as it iscustomary'in ,all boiler installations tovalve all pipes adjacent theboiler, butin the carryin out of the presentinvention, the valve really performs no function. l The balance tank Dis, adapted to `be vented when desired through a., pipe g in- I-cludi'ng the valve G, which may be regulated to permit the relief' ofvpressure through the pipe to the atmosphere or the venting` of thetank-D'. In practice, Athe y Water-level o the boiler is about that indicatedat min Figure 1 andthe head of \vaterwvith respect to the pipes a andbis designated4 by the reference X of Figure l.

Thebalancetank D may be provided with a suitablepres'sure vgage d andan-appropriate lgage glass J by lmeans of which lattor gag'glassl the-Water level in the. baly ance tank' may' be observed. Said tank isfurthermore' preferably provided -With a supplemental` valved outlet Madjacent the 'bottom' ofthetanky'the function of which vwill behereinaftermore fully explained.

C In practicing the method 'of the presentl.invention in an apparatus ofthe class described, all of the Avalves o1- thefsystem eX-l cepting thevalves 1F 'and K will .be closed G during: the normal `operation of theboiler.

rank1), the 'interior' of what, at this time, contains air atatmospheric pressure, with all other valves 'leading thereto closed;

This steam -warms up'the tank. D and gradually causesthepressureinteriorly of the tankto becomethesame as the boiler pressure of ltheboiler to be` blown bfi. yThe Valves A andJBv-.Will "novvy havesubstantially the same "pressure on their outer-side as on their. innervside and are consequently 7 in approximate balance. y

If it is assumed that the boiler A is, to be blown off, the valve A isnow opened and the Water flowsout of the boiler A through the valve Aand-through the *pipe ainto. the balance tank D and this flow of ivaterysov is occasioned purely by the hydrostatic pressure of the headand'is'in no Wise in-x y .lluenced by. ;-thev Working pressure of theboiler becauseo'fv vthe fact that the same. I' Working pressurehas been`tablishcd in the balance' tank.

Thisrelatively slow flow of the water from the boiler into the balancetank carries with it the sediment, boiler scale, mud'and otherimpurities contained Within` the boiler, so vthatt'hese impurities are"gradually- Washed from fthe boilerinto4 the balance tank. The engineerin charge of the operation 'Watches the gage ,glas'sJ,until, in hisopinion, orfthrou'gh experience, thev desired .previously eslWater-level has-been reached, which, in thevpresent-instance, maybe`designatedl by an the pressuretank,I whereupon Ithe valve A va'lve E,`which .has remained p opened to 'allow the displaced stea'mto' return`to the boiler, is closed.` Y, p Duringboth the;operations-jot openingand closing the valveA, this valve i's practicallyin balance and theusual objectionable stresses "to which such valves are subjjected arereinovedfrom the operating parts thereof. I- it should be desired forany lreason WhatsoeVerto cause the Water to flow lmore lrapidly throughthe blow-off ValveA than would be'due merely to the hydrostatic pressureof the head this velocity of elux can be increased b closing the valve EWhile=the ivater, is owing from the boiler.

andthen slightly opening th'e valve G, 'so y as to vent the tank. ThisWill throw the interror of the tank out of balance'by de- 'crreasing thepressure therein so that .the

up the flow'ofjwater therefrom;`

pressurewvithin the boilerwillserveto speed In the manner described, the'effluxA of -be .regulated as desired by `either keeping ing thevalve E-and openingthe valve'G to greater orlesser extentto govern the speed of,y Water through .the b low-oflvalve A can `iow of the Water. If thevalve G has been opened to accelerate the flow to tank D that tank isnormally brought back to boiler pressure by closing the valve Gandfopening the valve E before closing the blow off valve A. Nhile amanually-operated valve G is shown `as controlling the conduit g, itwill be obvious that such conduit Jmay be controlled by an automaticvalve-such as a float or ball operated to conform to water level in thetank, similar to the automatic valves described as associated withtheconduit e. lrloremrer, the velocity of the water through. the valve Acan actually be regulated so'as to be less than that normally caused bythe head, by leavingthe valve G closed and only partially opening thevalve llso as to throttle' the outgoing steam in the tank ,D` and thuscause back pressure in the tank D above the water, which pressure willbefcome greater than the steam` pressure in the boiler, thus retarding`the How through the valve A. l

Aft/er the .valves E and A are sealed.

n the valve Gr isopened to vent the tank D and thereafter the valve C indischarge pipe c is opened to permit the contents ot r'is desired todischarge the water more rapidly through the drain pipe C, the valve .Gmay be left closed and the rapidity ot eiiux of water through the drainpipe C can then be governed by opening the valve E more or less asdesired; or the valve E may be closed and the pressure in the tank onlypartially vented by opening the valve Gr for a short time.

It will of course be understood that the boiler B may be blown'oil1 Vinexactly the same lmanner as that-described with reier ence tothe boilerA by manipulating the valve B instead of the valve A, and regulating thevalve E of the pipe c which leads to the boiler B insteadl of thecorrespondying valve in the pipe which leads to the boiler A.

After ,blowing off the boiler. the construction described is such as topermit the engineer in vcharge to ascertain whether sui'- ficient waterhas been blown off to su'lliciently cleanseA the boiler. It is for thispurpose that the valved outlet M is provided. After the blown oil' waterhas been entirely discharged from the balance tank D through the drainlValve Ca test may be made as to the condition of the water remaining.in the boiler (as it is and as it will be affected by further opening ofthe blow oft valve) by closing the drain valve C and again opening theValve E to place the inl terior of the tank D once more in balance with`the boiler" to be tested. After the .i

blow-oft' valve and the valve E are closed.l

The valve G is then opened to vent the tank' and thereafter the Valveddraw-off M is openedv and the water which is containedv within thebalance tank is drawn off'intO any convenient receptacle, after whichthe valved outlet M and the valve sealed.

The water thus drawn off can be thor- G are again oughly examined by theengineer in charge' for the purpose of determining, by its condition,whether the amount of water which is being vblown off from the boiler istoo little or too much. dition of water blown ott', the engineer incharge can arrive delinitely and intelligentlv at the amount of Waterthat should be blown olf at each blow-off operation and can` withoutfurther inspection and tests determine how much Water should be blownoff per operation for Weeks to come provided, ot course,` that theanalysis of the .feed water going into the boiler l remains the saine,and that the amount of Water fed into the boiler per day remains thesame--as is frequently the case.

In the construction of Figures 1 and 2, one balance tank is utilized toserve a plurality of boilers, but if desired, a balance tank may beassociated with each individual boiler of a battery. Such an arrange`ment` I have shown Ain -Figures 3 and 4 of the drawings. The operationof the system of Figures 3 and 4 is identical-with that of Figures l and2, except that each boiler has its own balance tank. In thisarrangement, as well as in the arrangement of Figures l and2, the drainpipe c of theseveral balance tanks may lead to a common header c passingto the sewer.

A n important feature with particular reference to this construction isthat no'.`appreciable back pressureV is exerted upon the blow oi systemof any other boiler vwhen one boiler of a battery is blown offend,common'both to this system and theone previously described, is thefeature' that when one boiler is blown oil through t drain pipe commonto all the other boilers .of the By thus testing the conbattery, noappreciable back pressure is ex- 'erted in the drain pipe upon theblow-off valves of the other boilers. This condition is very desirable,and, in praetice,vit is particularly desirable that no steam pressure bebrought to bear upon the blow-oft' valve of one boiler due to theblowing oi of -an- .boiler might be shut down for repairs and the steampressure thus brought to bear on .the blow-olf vvalve would then be aptto leak through the valve and scaldor injure workmen in the interior ofthe first boiler. lVhen Apracticing the method described, the balancetank D is preferably vented, so that the water flowing through the drainto the sewer is under atmospheric pressure and Va boilermay, when thepresent invention is practiced, be opened and 'closed under properlybalanced conditionsin such man- .ner as tominimize the detrimentaleffects of wire drawing to which such valves have been subjected inprior practice. I have, however, vhereinbefore referred to shocks I"which, are occasioned by the sudden closingA yof the blow-ofi' valvewhen it is desired toconclude the blowing off operation, shocks may begreatly minimized'and practically precluded by closing'the valve E` soThese as' to preclude the escape of steam, while the blowing 'ofiloperation is in progress and before the tank D has vbecome filled withthel blown :off products. 'When this closing of the valvetakesplace, thefurther escape. of steam from the tank into the boilerii's precluded andthe steam which remains in the tank isV slowly compressed as the blow-j'off operation continues until 4the pressure of said residual steamsubstantially balances the steam pressure within the boilerplus thehydrostatic pressure of the head, where upon water flowing through theblow-ofi valve will slowly come to -a stop. The blowoff' valve may thenbe closed without being Y subjected to the force of the .blow of amovingcolumnl of water'l as heretofore, and' without being subjected to anywire drawing effects. z Y

The exhaust of steam from'the tank may be controlled automatically. Inthe showing of Figure 5, the .pipe c is shown as eX- tended through'thetop of the balance tank D. and for an appreciable distance downy' wardlyinto 'the interior ofthe tank and on theflowerend of this pipe a cage eis sup-l l ported, in which cage is positioned a ball 'valveE in Vtheform of a float.- In this -construction, it will appear that as thewater ylevel rises in the pressure tank., it will -'lift theball valve Eand cause the same to.seal the lower end of the pipe e. The

y)flow of further water into the tank will.

manifestly compress the trapped steam therein until the pressure vofthistrapped steam becomes the same as the steam pres- A0, fixed to theoperating post.

'the blow-off valves may be positively locked against closing until suchtime as they may be closed without producing shocks.

In Figures 6 and 7, apparatus is shown for accomplishing this result. Inthese figures, the operating post of the main blowoff valve A isprovided with a locking cam The cam is provided with a shoulder withwhich a shoulder dog L is adapted to engage. Thev dog L which is pivotedat one end at Z is secured at its opposite end to thelower end of a linkN, the upper end of which has slotted engagement with an arm O fixed onarock shaft o which passes into the tank D and is provided with asuitable stuf'ng box to preclude leakage of pressure, and a suitablestop r'oto limit its downward 'movement The-rock shaft o carries on theinterior of the ,tank an arm p to the outer end of which is fixed 'afloat P. In this-construction, the

Vtank is also provided with theball valve E,

shown in Figure 5. AS the water flows Afrom Athe boiler intorthe balancetank D, it

simultaneously -raises the ballA valve E', and the float P, and the linkN is of such length that the float will not influence the dog L untilthe valve .E has becomev seated. Asl

time, the' operating stem of :thefvalve has been locked, so that ,thevalve could not-be closed, but as soonl as the dog is raised, the valvemay beeasily-moved to a closed .pOsi-- tion.

The mechanism described is I simple in construction .and efiicient inits operation,

since, when once properly regulated, it will positively operate to lock.the valve against closing 'until such time as the. pressures arebalanced and the iow yofwater through the valve 'A vceases. `Wh'enthismechanism is employed,shocks which have been heretofore common arerendered impossible.

There is another feature connected with the operation of the blow-olfvalve which isvcomplementa'ry to this arrangement, and that'is that thevalves being balanced, and

when they shouldv be operated, can be equipped with operating means suchthat at all other times than the time they should be open, they cannotbe openedby theordinary .consequently ,easy to operate, at the time Ivoperating means. It is thus impossible for a careless or stup1doperator to make a mistake as to lwhich `blow-off valve, or which valve,he should open to blow ofi" a given boiler which he has prepared tovblow-off under this system. LReferringto Figure 3 let us designate by Zthe lever by which the blow-off valve Ais operated.

Under ordinary blow-offl conditions the lever Z must be made long enoughso that a man of ordinary strength can,.by means of it, open the valve Awhen the :boiler is under full steam pressure andthe valveunbalancedisunder the same pressure. Therefore,at any time, arman of ordinarystrength can open the blow-ofi' valves of any boiler, in cases vwherethe ordinary operating I. means is left attached to the valves betweenthe periods of'blow-of.

yUsing the system described in this specification. with the specificaddition now described, it is not possible for anyone by using theordinary operating means, to'open any `blow-olf valve ofa boiler underpressure unlessand until he has prepared'that boiler for blow-off byputting the bilancing means into operation.' Asv the valves openpractically without resistance when they should be opened, the operatinglever Z (or an equivalent hand wheel in the screw operated type ofgvalve) -can be made so small that only when the valve is in balance canit be opened by a man of normal'strength using the attached :and regularoperating means; and lfurthermore it is practicable to deliberatelyinsert a breaking point into the operating mechanism lso that if anyoneattempts, b

rdgular operating means, to open the valve when it is not in balancedcondition, the opl erating means will part fromthevalve or break off,leaving the valve in perfectly `unharmed condition-as a valve, but nowoperable' only by calling on the engineer in charge who has thenecessary supplementary apparatus of special character by which thevalves can be operated.

In the apparatus herembefore described, a balance tank is provided forthe eiiicient lcarrying out of the method of this invention,

but I have found that many-advantages may `be'obtained withoutnecessarily employind the balance tank and by using apparatus (ifVthegeneral character shown in Figure 8 of the drawings. In thisconstruction, the bal-` ance tankmay be omitted between the valves A andG and these valves connected by a length of pipe c2 with which the steampipe e connects.' In this construction, the valve 'C may be'of anydesired type and m-ay be in leaky condition without affectingv theproper operationof the apparatus, provided, however, that the pipe e isof suflicient size to furnish steam to the pipe c2 in excess of the useo'flong levers faste-ned on to the balanced condition. As soon as theblow ofi' .valve A is. opened, the valve E is closed and the valve Cmaybe opened so as to blowoff the boiler directly? through 'the drainpipe. When, in lthe opinion of the engineer, suflicient water has beenblown off to properly cleanse the boiler, the valve C is vclosed and thevalve E again opened and left opened, whereupon the opposed Huidpressures of water and steam assume an approxsol imate balance and thevalve A may then be closed or closed later when the'tluids are at rest.The valve E can be lsubsequently closed.

yThe methodwhen practiced with the construction of Figure 8 will prolongthe life of the valve A by minimizing erosion due to wire drawing andwill also minimize 4the probability of breakdown of the operatingmechanisms of the valve A- by relieving them of stress since said valveis in substantially balanced condition duringthe ope'ning and closingthereof. It will be apparent, however, that while this construction is amarked advance overpri'or'practice, it

loo

is not capable of performing the .important functions of the; balancetank D, which, in accordancepwith this invention, preferably forms apart of the blow-off mechanism.

In Figure'Q is illustrated another system 1 of conduits and valves forcontrolling the pressures in the tank I). By this arrangementA theinterposed valve A is balanced by reason of both hydrostatic and steampressure. In this construction the pipe c forms a connection between thesteam dome of the boiler and top of the tank D and the valve E isinterposed therein above the water y level in the lboiler X. A pipe g isthen connected with the pipe c below the valve E and between that valveand the plane of the water level in the boiler ,X, a valve 'G is interposed in said pipe g.

The method is operated under this construction as follows: closed andthe valveE open, the valve A is placed in substantial balance asheretofore described. When the valve'A is opened the water from theboiler is blown ott1 against the steam pressurev and the water rises inthe tank D and pipe e untilit iinds its level in a plane correspondingwith the water The valve G beingv Figure 8, as Well as to certain'iotherligures v to flow and the valve` I is .in practically complete balanceas the steam pressure plus vthe hydrostatic pressure `are equal .oneither `side of the valve and under these conditions 'said valve may beopened or closed withthe minimum of resistance.

When under such conditions the valve A -is closed, the valve E canbe'closed and ,the valve G' opened to the atmosphere so that the tank'Dmay be drained. K f

From what has been said with reference to of the drawing, it will bemanifest 'that the method of this invention embodies diderent series ofoperations certain otwhich may be practiced without necessarilypracticing them all in sequence. Accordingly, thein.- vention is toA beunderstood as notjlimitcd to all of thesteps enumerated, butvis be con;Astrued as broadly novel as is coInman-Surat;ey

with the' appended claims. l. The foregoing is a' preferred arrangementof apparatus Vadapted for the' performance@ of the various steps orstages ot the 'method or system of boiler blow-off above described. Aspreviously stated, the same may be varied to accomplish the same result.(Jheef-the notable variations which in .act'reducesf'the fr operation.down to itselemental'principl will be obviouswhen consideration -ls gi'to an arrangement wherein all those mean, s` previously described forintroducing' in-to* the tank D gas Or-steam under pressure' areeliminated, 'and the tank'D is consideredas a container filled with airunder latinos'- -f eillux through-'the:exhaust 4with the resultpreviously statedthat the water, instead of carrying yo'l' v'the mud orother sediment, will form apertures through `the-same and iindv phericpressure. In 4such case, assuming pheric pressure, the opening ofthevalve A will permit the elu'x-of water .from the boiler into saidtank D, Aand Vsuch efflux will be cushioned .by the `air Withinl sai-d..ftank..

until saidl air reaches 'a stage at `which it balances the steam andhydrostatic pressures in the boiler.

result from such closure. The valve G can `then be.openedto vent thetank D and a` portion of the contents or the whole contents can bewithdrawn from the tank D for the purpose of inspection and test,-andany balance withdrawn through the pipe` c under its own hydrostatic:pressure. 'Ihe' operation can be repeated from time toI time until thedrawn ofi' water is-fo nd to be of proper consistency. This I regard asan elemental feature of m invention. When I introduce The valve A`canvthen .be closed, the samebeing in a state oibalance'.- As noeftluxis-taking place no shock `will in approximate'balance',f andfurthermore,

through the medium of'said valve E, I can according to the operationabovedescribed control the rapidity of the eilluX of the water fromthe-boiler 'to the blow-off tank, and

through the medium of the automatic valve devicesmheretofore describedI' can automatig callyieojntrol the valvesernpleyed by utilizingthciwater level in the tank for such purpose, that is to say through themediumA of a lfloat I can-lock the valve so as to prevent its closureduring a ypredetermined periodl and through the ball valve I can cutofi1 the exhaust from the tank D. As illustrated in Figure S I may varythe apparatus and accomplish partial results by eliminating the` tank Dand confining the 'operations to the pipes C2 and e as stated. l' Aspreviously stated, one of the object-s oi '-my invention is to providea.- method by which the powerful elements with which it 'is' necessaryto deal can be brought into absolute control to accomplish the enddesired. The primary object in blowing ofa boiler' is ,to eliminate thesludge or vscale and dense vcnaterA which accumulates at the base of theoiler. .Toaccom lish this result it vis ime* `absolutely under control,so that it may caused to moveislov'vly, to-theend'that it Willicarrywith it the body o f heavy. sludge boi-le'r-,Qas'fopposedv toanfunrestrained 'rapid joitantthatthe e ux from the boiler should -itsway to the exhaust .Without the accompaniment of the heavierelemcntsfreferred to. The Word slowly used above with refthrough themedium of the operation of the valves E and G the'rate of thiseiiluxshould be entirely under the control-of the operl ator, in order toUnder some cpnditions it is conceivable that it may be deslrable tolimit the eiilux to one rate ofjspeed, while under other conditions, 4

roduce the best results."y

it might be desirable -to increase or diminish 4 'that rate. vIt will be,obvious that by eX- periment under each set of conditiona'it will befound'possible to regulate and determine what degree of velocity is mosteflicient .in scavenging the boiler.

Thestatement has been made that one' lot the' objects of the inventionis to relieve the interposed blow-oli valve of undue pressures, so as toavoid'jinjury to the valve 01p-v erating mechanisms moving the sealingmember to the open or closed position under isc the great 'stresses dueto the boilerpressure.

.I accomplish this result in the operation of my invention by theapproximate-balance which I establish between the steam and hydrostaticpressure on one side of the v alve l and thesteam pressure ontheothenthu'sleaving the valve 1n approximate balance and by so doing,makingit possible to operate the valve to open land close the sameVunder conditions of the minimum of resistanee. By the establishment'ofthe foregoing conditions' of balance particularly when. combined' withcessation of flow before 'the valve'is` closed, it will be apparentthat" I, also minimize the element of shoclrwhich,

uider other conditions, lis brought about when the valve is closedbecause of the fact 'that the eiiiuent columnfof water operates as ahydraulic ram.

That .theseV are all beneficial results -will be obvious, but I desireto point out specilically the method -that I recommend for. theascertainment at any time of thestate of the fluid in association withthe heavier `materials which accumulate at the base of the boiler andparticularly as to` Whether lenough-too much-for too little has beenblown oif. To attainv this result I proceed' in the manner heretoforeindicated and draw oil' -av portion of water from the boilerthis'may bemore or less. Preferably in the first instance I may fill the blowofftank D and, having exhausted the same, 1

repeatthe operation, but instead of drawing the full capacity of thetank I may drawonly a few gallons of water from the boiler. Thls watercoming, as stated, at apredetermined rate of speed ifrom the boiler willbe- -a practicallyl accurate sample of the effluent when blowing off,and a repetitionof this process successively will demonstrate how lessand less, until the observer is satisfied much Water should be blown oflto bringthe.

boiler .contents to the desired condition, that is to say, ranobservation or test of the water will show that the density ofthe waterand the amount of sludge or residue is becoming that the water in theboiler is sufficiently free of foreign matter and too dense water tosatisfy the requirements of the case, as far ast-they can beeconomically satisfied by blowing off. AFurther z-by sampling thecfiluent at various speeds of discharge from the boiler the speed whichgives the maximum discharge ofl sludge, scale, etc. from the boiler canbe ascertained and used.

From the foregoing it will be understood oil` so as to get the bestresultswith the minimum loss of hot water (now hot water is4 equivalentto coal, and coal is equivalent to. money).

The operator is able to obtain these results because he is ablev tofindlout at what speed of elilux maximum scavenging takes place withminimum expenditure of hot water, and is also able to 4scientificallydetcrminethe amount of water which should be drawn ofl` through theblow-oil' lvalve in any given per.iod,land, having' ascertained the bestconditmns legis able-by this invention-to obtain them.

Under present methods it is impossible to ascertain the-facts, and evenif the facts.

were ascertained it is practically impossible to obtain the necessarycontrolwithout subjecting the blow-off valves to Asuch severe conditionsthat their life as operating vvalves would be exceedingly short.

The foregoing observations lead to a con'- sideration of the advantageso f this method from the standpoint of economy of boiler operation. Aspreviously stated, under the present' system of boiler, blow-olfpractice it is impossible for theoperator to ascertain with any degreeof certainty the'amount of water which should be withdrawn from theAboiler during the operation of blowing olf, and too little blown offmight have most detrimental results. He therefore makes sure that heblows off plenty, the result being that a large amount of heated wateris vfrequentlyunnecessarily withdrawn; in so far as such excess isunnecessary it is an extravagant waste of heat units; that-is to say,losses of heat/(which are equivalent to losses of coal, which areequivalenttolosses of money) due to the blow-offvalve beingopen too longand these losses will be much 4greater* under conditions of 350 poundpressure than under conditions of 200 pound pressure or less. Loss ofwater ismueh more. -serious than the loss of the same volume of steambecause every cubic foot of water is vthe equivalent of approximatelytwenty cubic feet ofsteam,so that,as stated, the loss of a given volumeof hot watcr'from a boiler is always more serious than the loss of asimilar volume ofsteam, as will be apparent from the followingcomparison of the loss dueto blowing off one gallon (roughly 8 cubicfeet) of water at 434 Fahrenheit, being equivalent to a working pressureof 350# per square inch, with the loss due to the escape of 8 cubicfeet. of- I steam at 4349 Fahrenheit being the temperature equivalenttoa Working pressure of 350# per square inch.

8 cubic feet of water weighs roughly 8 multiplied by 63 or 50414:.

The temperature of the water when it entered the boiler waslproba'bly200 Fahrenheit.I Consequently in the boiler the heit to 434 heit.

' guapos water has been raised from 200.o Fahren` Fahrenheit, or 234Fahren- To. raise 504# of water 234 Fahrenheit requires 234 multipliedby 504 B. t. u.s o r 117,936 BL t. u.s.

8 cubicfeet of steam'at 359# (onecubic foot weighing .79#'say .8) weighs6.4#.

The latent heat (heat required to transform one pound of water at'434'Fahrenheit into steam at 434 Faghrenheit)v 'ofi i steam at 350# pressureis a trifle-under 800 B. t. uns. .cau a. 149e ngt.' afs.

Fahrenheit and 20' B. t. u.s. Let us call it 800 Bit. vuis, The latentheat therefore of 8 cubic feet of steam is 6.4' multiplied by 800 or5120- Heat lost in 8 cubic feet of wat-er from the boiler` shown'to be117 ,936 B. t. u.s, heat lost from 8 cubic feetof'steam escaping 'fromthe boiler has just been shown'y to be 1498 lus 5120 or 6618 B. t. u.s.

The oregoing will demonstrate the iinportance of conserving the volumeof water blown out of the boiler for the purpose of scavenging the same.One of the objects of the method and system which formsthe subjectmatter of this Tinvention is to con serve the volume of water permittedto es' cape so as to limit the same to the minimum amount of waternecessary for the accomplishment f the result.; For this purpose Iprovide a blow off tank as`D -Which may in fact form the unit of measureof the amount of water lthat I elect to draw-from'the -tank at one time,and I may repeat thiso'peration as often as it may be found necessary,or as previously stated,.I may limit the flow of waterto thetank'D so asto withdraw ,from the boiler only a 4few gallons of water sulficientfor.the purpose of observation and test, so that in the operation of.the method the operator is in complete control of the volume ofwaterpermitted to escape from the boiler and the y velocity of itsescapeso that he is alsoin control of the eiiiuent water so as to bring the`same under conditions where it' will be the most eicient a ent inconveying the sedimentrom boiler into the blow-oft' tank., v

Aside from the economic and mechanical advantages secured by the method,or methods, or 4 procedure described, attention is called to the factthat the various operations can be carried out with relatively litt-ledanger 'to the operator, .whereas the present methods of operation areextremely danger'- ous and quite frequently result in serious .accidentsand lloss of life. *It is manifest, therefore,- `that the presentinventionembodies lavdistinct advance from the .stand- .point ofconserving the safety and life of steam. boiler operators and associatedworke1s.

described will'be.. capable ofmodiiication by those skilled in the art,suchas .by the substitutionof equivalent steps oroperations,withoutdeparting from the spirit'v or substancefof the-invention, thescope of which is commensurate with the appended claims.

It will-'Abe understood that 'the invention Moreover, the apparatus andmechanism herein described constitutes a partof the present broadinvention. Having thus fully described the invention, whatI claim asnewand Adesire to secure by Letters Patent is :v y r 1. The method orsystem of boiler blowo'ii" whichvrconsists in releasing'the-waterunder'pressure against a gaseous cushion conned within a suitablecontainer, then cutting oil'. such supply" of water, and venting thecontainer of gaseous Huid, then drawing off the fluid from the containerfor pur.- poses of observation, testl and -discharge. f

2. The method: or system of boiler blow-l off practice which consists inproviding a sealed tank, and means for creatin and regidilating gaseouspressure within sai tank, an

.and the basefof the boiler to permit the efiiux of water from theboiler to the tank, with a valve interposed in said conduit, thenadmit-V ting gaseous pressure into the tank Aand conduit to.approximately balance the boiler i pressureon the opposite side of thevalve and to control theow of the water which is adapted to ow from theboiler to the tank after said valve is-.opened, then opening said valveto permit thevioW of water from the a conduit interposed between thetank v boiler to the tank, then closing said valve,

`ing the gaseous pressure within the tank, and drawing .off the contentsof the tank for purposes of observation and discharge.

while in approximate balance, and diminish- 3. The m'ethod orisystemofboiler blowoff which consists in providing an auxiliary receptacleorchamber connected to the boiler blow-off pipe,'which connection iscontrolled :by a suitable valve, then -connecting said auxiliary chamberto a source of gas under 'pressure s'uiicientlto approximatelycounterressure of the water adapted to" pass to the chamber through the boilerblow;y

1 oit' connection, and, Ifrom the source of gas,

filling said auxiliary chamber with said gas balance the under pressure,then openingthe valve to permit .the flowlof water from the boiler-'tothe auxiliary chamber, controlling 4the ratev of such flow of water bycontrolling the escape of gaseous'pressure from the auxiliary chamber,-then closing the valve to shut off thelow ofwater from the boiler, thenshut# ting olf the course ot' gaseous pressure, and thenventing theauxiliary ehan'iber ot such gaseous pressure, and' drawing oil thecontents of theauxiliary chamber lor purposes ofv observation anddischarge.

4. The method or system of boiler blowoti' which consists in releasingthe liquid under pressure against a steam cushion'talren from the domeof the boiler and contained lwithin a` suitable container, then cuttingoft the supply of liquid ilowing from the boiler as well as the steampressure from the boiler, and Venting the container of the steamcontained therein, then ,drawing oly the liquid'trom the container torpurpases of observation, test and discharge.

,. /5. The, method or system ot boiler blowoil which consists inproviding an auxiliary receptacle or chamber connected to the boilerblow-oil pipe, which connection is, controlled by a suitable valve,then. connecting said auxiliary chamber to the steam dome of the boiler,and, through the last mentioned connection, transmittingstean'inpressure to said auxiliary chamber, then opening said valve andpermitting the eillux etwa-.ter Jfrom the boiler to the chamber, suchflow being con-4 trolled by-permittingthe steam to return at a desiredrate tosaid dome from said chamber through theeonnection between 4l hesame` then closing .the valve controlling the flow ot water whilesaidValve is in a state ot balauffe and shutting off the source of steamsupply, and then Venting thev tank ot such steam pressure to theatmosphere and drawing off the contents of the tank tor purpose ofobservation and discharge.

6. The method or system of boiler blowotf which consists in releasingthe liquid from the blow-.oit pipe against a gaseous cushion containedwithin a suitable container, such cushion being torni-ed by steam takenfrom the boiler and controlled as regards the extentl ot its pressure toapproxoft which consists in communicating gaseous pressure through a'suitable container to a boiler yblow-oilqv valve so as to place saidValve-ina state of approximate balance, then opening said Valve, whilein balance, to per- `mit liquid to flow from said boiler into saidcontainer and at Athe same time cushioning the flow of liquid againstsaid gaseous pressure to control the rate of the flowthereoh thenincreasing said gaseous pressure to are restsaid flow until the columnof .liquid is l brought to a state of approximate quiescence,

then closing said valve while in balance, then chamber and said outletbe'tore the rblowoil' valve is op.\ne l,so as to place the Valve insubstantial balance betere opening the same, thereupon opeiiing theValve to permit water to flow from the boiler into the chamber, andthereafter pern'iitting a portion of said gas under pressure to iiow outo'i' the chamber until substantially the amount ot water which it isdesired to draw oi'" troni the boiler .has entered the chamber. thensealing the chamber to preclude the exit of further gasl` so that theflow of turther water into the chamber compresses the trapped gas andproduces suiiicient back pressure to stop the flow of water from theboiler into the elian'iber, then closing the blow-oit valve, andthen'permitting the water in the chamber to flow out of the same.. 9.The herein described method of blowing oli' a boiler through a valvedoutlet into a substantiall).v closed chamber, which consists in sendinggas under lnessu're into said ehzunber and said outlet betere theblow-ott ralve is opened. so as to place the valve in substantialbalance beiore operating the same` thm'eupoiry opening the valve topermit water to flow from the boiler into the chamber, and thereafterpermitting said gas under pressureto flow out of the chamber untilsubstantially the amount of water which it is desired to 'draw ofi' fromthe boiler has entered the chamber, then sealing the chamber to precludethe. exit ot' lurther gas, so that the flow of further water into thechamber compresses the trapped gas and produces sufficient back pressureto stop the flow of water from thev boiler into .the chamber, thenclosing the blow-ott valve, then venting the chamber, and thenpermitting the water in the chamber lto llow out or" the same undersubstantially atmospheric pressure.

l0. The method or system ofboilerblowoft which consistsin communicatingsteam pressure, led from the boiler and through a container, to ablow-off valve positioned in a connection between the boiler and thecontainer so 'as to place said Valve in a state ot approximate balance,then opening said Valve while in balance to permit the flow of liquidfrom the boiler to the container through said connection, and cushioningsaid flow of liquid against said steam pressure to control the rate ofthe owlthereof, then causing an increase of said steam pressure toarrest said iiow and to bring the liquid to a state of substantialquiescence, then closing said valve while in balance,

then releasing said steam pressure on said Withdrawn liquid andpermitting the liquid to flow from the container by gravity.

l1. The herein-described method, which consists in-blowing ofi" a boilerinto a substantially closed chamber andvcontrolling the velocit-y of theflow of Water from the boiler int-o said chamber by regulating thegaseous pressure within the chamber, then cutting ofiq the flow of Waterfrom the boiler toV thel chamber, and regulating the verlocity of theexhaust of Water from said chamber by controlling the gaseous pressureWithin said chamber.

12. The Amethod herein described which consists in blowing 0E a boilerinto a closed chamber, said chamber being lled with supply of gas underpressure, and the degree of such gaseous pressure being under con--trol, and regulating such gaseous pressure Within the chamber to controlthe velocityv of the flow of Water from the boiler into the chamber,.then cutting off the supply of Water to the chamber and regulating thevelocity of the exhaust of Water from said chamber by controlling thegaseous pressure Within saidv chamber.

17th day of October, 1921.

' WYLIE G. WILsoN.

lVitnesses: l

DOROTHY FRANK (SCHEIBER), SADIE H. OLIKER.

